Before using an essential oil, you should be aware of its possible adverse effects. Aromatic plant distillates have been used for over a century as food additives, as well as in perfume, cosmetics, soaps, etc. The FDA is the regulatory body in the United States, and most essential oils have the G.R.A.S. (generally regarded as safe) designation. The following is basic safety information regarding essential oils in general, and further considerations can be found on the Samara Botane Essential Oil Monographs.

Essential oils that are considered too toxic for aromatherapy are Bitter Almond, Brown and Yellow Camphor, Rue, Tansy, Wormseed, Wormwood and Sassafras. Other oils that could be considered hazardous are Cinnamon leaf, Cassia, Pennyroyal, Thuja and Mugwort. Essential oils that have not been safety tested and need caution are Amni visnaga, Catnip, Chamomile, certain Eucalyptus chemotypes (E. globulus and E. citriodora are the only ones tested nontoxic to date), Inula graveolens, Kanuka, Manuka, Melissa, Niaouli, Ravensara aromatica, Rosemary chemotypes except the common cineol types, Spikenard, Thyme chemotypes other than phenol, Valerian and Yarrow. Essential oils that have been tested and do need caution are , Benzoin resinoid (sensitizer), Bergamot (photosensitizer), Calamus (banned in cosmetics), Cinnamon bark (powerful irritant and sensitizer) Copaiba or Copahu (sensitization), Inula graveolens (sensitization), Peru balsam (sensitizer), Tagetes (sensitizer),

Researcher Martin Watt advises us that there are three adverse reactions to consider when essential oils are applied to the skin:

  1. Irritation: This is when a substance comes into contact with the skin and causes anything from a mild itch to a burn, almost immediately. Usually, once the substance is removed, healing takes place and there should be no further problem.

  2. Sensitization: This can be much more serious than irritation. Once the substance has been introduced to the skin, it can cause permanent cahnges in the immune system in a similar manner to a vaccination. Symptoms may not occur until time passes. Once the body has become sensitized, a reaction may occur the next time the substance is introduced. Sensitization can appear in varying degrees of severity, from a mild itch to severe anaphylactic shock. The latter in aromatherapy is almost unknown. To be safe, however, if after using any essential oil or absolute, an irritating or burning sensation, or blotchy irritable skin rash are noticed, then that particular oil or chemically similar ones should not be used again. Sensitization is not common.

  3. Photosensitization: (Sometimes referred to as phototoxicity). This is where a substance coming into contact with the skin can react with ultra violet light. This reaction can cause anything from mild brown blotches to severe burning of the skin. The condition can be long lasting, and the condition can recur after exposure to ultra violet light. The main essential oil to avoid in this respect is expressed Bergamot, however, it is wise to be cautious with all Citrus oils.

Pregnancy: There are many claims in aromatherapy books about not using certain essential oils during pregnancy that are unfounded. Oftentimes information attributed to the effects of essential oils are from research data regarding the water-soluble extracts of the plant, taken orally. Used in moderation, with common sense most essential oils used in aromatherapy are safe to use in pregnancy. The exceptions would be birch and wintergreen oils. Clary sage should be avoided by anyone with a history of early miscarriages. Please remember that any aromatherapy treatment will affect your baby if you are pregnant or nursing. KEEP OUT OF REACH OF CHILDREN.

Epilepsy: It is true that any strong smell can and may trigger an epileptic incident. However, some trials have indicated that relaxing oils can substantially reduce the incidence of attacks. Therefore, it may be advisable to avoid pungent oils like camphor, eucalyptus, tea tree, rosemary, etc.

High or Low Blood Pressure: There are no scientifically verified trials published, following the external application of essential oils. There are also no proven cases of anyone that has suffered ill effects from escalation of blood pressure caused by aromatherapy. Generally, an aromatherapy massage will decrease blood pressure that is high due to stress.

Safety levels have been ascertained for the most common essential oils used in aromatherapy. Diligent aromatherapists should inform their clients about those that have not been tested. There are no ‘traditional’ uses of essential oils, and these reports are those reflecting the use of the herb and not the essential oil.

More is not better with essential oils, and they should be used in sparing, minute amounts. Body size, weight, age and state of health can determine dosages.

Oxidization and rancidity can cause toxicity. Refer to CARE OF ESSENTIAL OILS.

TREATING EMERGENCIES:  If an essential oil is accidentally splashed in the eyes or on sensitive skin or mucous membranes, immediately douse the affected area with olive oil.  This acts as an absorbent fat, binding to the essential oil, diluting its effects and enabling removal.  Other vegetable oils or aloe vera gel can be used as an alternative.  NEVER USE WATER TO DILUTE AN OIL BURN; this will only disperse the essential oil increasing the area of damage.  After removing the olive oil from skin and around eyes with a damp cloth or tissue, you can wash skin with gentle soap and water.  


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